Normal capillaries are composed of endothelial cells and pericytes and serve to transport blood to all body tissues. Neovascularization, or angiogenesis, is the growth and development of new capillaries from existing vessels. Angiogenesis is essential for the initial formation of the vascular system as well as for reproduction and wound healing. There are, however, conditions characterized by unregulated persistent neovascularization, including a variety of tumor cancers, diabetic retinopathy, neovascular glaucoma, rheumatoid arthritis and psoriasis.
It is therefore desirable to understand the molecular basis of angiogenesis, as a basis for designing therapeutic strategies for treating conditions, such as cancer, characterized by unregulated, persistent neovascularization, or conditions, such as wound healing where increased vascularization is needed.